Eleoteic arc lamp



(No Model.) 2 Sheets--Sheet 1.

- E. THOMSON & E. W. RICE.

ELECTRIC ARC LAMP. No. 440,663. Patented Nov. 18, 189.0.

,Ziy 1742' m :4.

(No Model.) 2 Sheets-Sheet 2.

E. THOMSON & E.-W. RICE.

BLEGTRIG ARC LAMP.

Patented Nov. 18, 1890.

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UNITED STATES PATENT OFFICE.

ELIHU THOMSON AND EDWIN WILBUR RICE, OF LYNN, MASSACHUSETTS,

ASSIGNORS TO THE THOMSON-HOUSTON ELECTRIC COMPANY, OF CON- NECTICUT.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 440,663, dated November18, 1890.

Application filed January 3 l 8 84.

in Electric-Arc Lamps, of which the following is a specification.

Our invention relates to electric-arc lamps,

and is designed especially to simplify the construction and operation ofarc lamps and at the same time to permit the ordinary feedregulating orcarbon-adjusting operations to be controlled by the current in ahiglrresistance derived circuitonly, acting in opposition to aretracting spring or weight, instead of making such operations dependentupon the differential action of main and derived circuit coils ormagnets, respectively, in circuit with the carbons and inahighresistance derived circuit around them.

Our present invention relates to certain improved details in electriclamps of the form in which are combined a feed-regulating armature orlever from which the carbon or other electrode is suspended orsupported, a derived-circuit coil of high-resistance acting on saidlever in opposition to a suitable retractor to control the position ofthe electrode, a starting or assisting coil or circuit through whichcurrent flows at the start to bring the said carbon-supporting leverinto properlyacting position, and a switching device for switching outsaid coil or circuit directly dependent upon the establishment ofcircuit through the carbon or electrodes.

Our invention consists in certain combinations and arrangements ofdevices designed to simplify and improve the operation of the lamp.

The invention will be described 1n general terms in connection with theaccompanying drawings, and will then be more particularly pointed out inthe'claims.

In carrying out our invention we prefer to use the electro magneticeffects of the current in the starting-circuit to produce the desiredoperation, but do not limit ourselves in this respect, as we may use anyof the motor Serial No. 116,331 (No model.)

effects of a current and may therefore produce the desired results bymeans of a thermostat or other device actuated or energized directly orindirectly by the heating effects of the current flowing through anartificial resistance in the starting-circuit.

In the accompanying drawings, Figure 1 is an elevation of an electriclamp containing our invention. Fig. 2 is a plan of the same. Fig. 3shows a modified disposition of the coils. Figs. 4, 5, and 6 show otherarrangements for carrying out the invention. Fig. 7 shows how theheating effects of a current in the starting-circuit may be utilized forthe purposes of our invention.

Referring to Fig. 1, E E indicate, respect ively, the-positive andnegative carbons of an electric-arc lamp, and R the carbon rod orcarrier supporting the positive carbon and engaged by any suitable feed-regulatin g mechanism. That here shown consists of an ordin'aryclamp or clutch constructed according to theinvention of E. Thomson, andcomposed of a clamp body or guide C, through which the rod B may move,apivoted clutch or jaw T, pivot-ed 011 C vand normally engaged with therod by a spring Z, so as to prevent the rod from moving downward throughthe clutch, and a releasing-stop F, with which an arm of T engages whenthe clutch is lowered sufliciently, so as to permit the rod and positivecarbon to move downward. hen the clutch is raised bodily by any meansaway from the stop, the carbon is raised with it. The clutch may bereplaced by any mechanism which when moved in one direction will raisethe carbon and when moved in the other-will re-. lease it. v

L indicates a feed-regulating armature-lever, which serves to impartmovement to the clutch, or feed-regulating mechanismin any proper1nanner-as, for instance, by a link D.

S indicates the retractor for the armature, which retractor, whenunopposed, lifts the clutch, and with it the upper carbon, while Bindicates the armature of a derived-circuit magnet of high resistance,whose coils are indicated at K, and which acts in opposition to theretractor.

The armature is perforated, and the pole of the magnet is conoidalorparaboloidalin form, as described and shown in a prior patent grantedto E. Thomson, so that with the same strength of current the pull uponthe lever L will be the same in all positions of the armature. The coilK is in the usual derived circuit around the carbons, which circuit isindicated by the numeral 5.

G indicates a starting-coil, the object of which is, when current isturned on, to pull down the lever L and cause the carbons to cometogether. It is preferably of low resistance and wound upon the samecore with coils K, so that at the start it will strongly magnetize thecore acting on armature B.

Coil G is in the present instance in abranch around the carbons, whichbranch is indicated by the numeral 6 and includes the contactpoints I)of a switch or circuit-controller lV, upon which a retractor Z acts, soas to tend to keep the contacts I) closed.

As will be observed, the coils K are in a circuit around both G andcontacts b, with the double effect that the opening of contacts b canonly affect the circuit of G, and that the spark of rupture, if anybeproduced, will be taken up and absorbed by the coils and core of K. Theabsorbing or neutralizing action is also largely increased by theplacing of the coils G and K upon the same core, which coils are thenrespectively related to one another as the primary and secondary of aninduction, coil, whose secondary current will flow in local circuit withcontacts I) and will neutralize the spark'of rupture. The branch 6 is,as obvious, abranch around the carbons.

The carbon-circuit at some point between X and Y contains thelow-resistance magnet M, which when energized acts upon its armature N,attached to circuit closer and controller W, and if the contacts I) areat such time closed will open them and hold them open, so as to open thecircuit of coils G and render the latter inactive. Magnet M obviouslyacts only when the current flows in the carbon-circuit with E E. Atother times, as when the lamp is out of action, the circuit of coils Gis closed by the spring Z The magnet G K mav obviously be a single-coremagnet or a double or horseshoe magnet, as indicated in Fig. 2, each legof said magnet being wound with two coils G and K, or one leg carryingone coil, as G, and the other leg the other coil, as K. When the lamp isout of action or no current passing, the parts are in the position shownin Fig. 1, the lever L- being retracted to an extreme position, so as toraise the clutch and hold the carbons separated. The circuit of coil Gis closed through contacts]; by the action of spring Z The operation isas follows: /Vhen the current is turned onto the circuit containing thelamp, the current from X, finding no circuit at E E, because the carbonsare separated at the start, passes through the coil G, through contacts12, and out at Y. The magnet G K then attracts its armature B B,lowering and releasing the feeding mechanism and dropping the carbonsinto contact. At this moment the magnet M is energized by the currentpassing through the carbons and attracts its armature N, opening thecircuit of coil G at 12 against the action of retractor Z The coil G isnow out of circuit and ineffective, while the contact I) is kept open bythe passage of current at E E. An arc is now formed by the retractileforce of S, lifting and locking the clutch O and raising R untilrestrained by the increased force of derivedcircuit coil K upon B 13,due to the increase of resistance between E E. The lamp now acts to feedby the sole agency of K. The stoppage of current in the lamp restoresthe parts to their original positions.

It is not necessary that G K be wound upon the same magnet or the samecore; but they are preferably so wound for simplicity. Two magnets maybe used to replace the combined magnet G K, and two armatnresB Battached to L, as seen in Fig. 3. Many other equiva lent arrangementsare possible. Instead of pulling L down, the action of G may be todepress thelever L indirectly by slackeningtemporarily the spring S.Such a construction is indicated in Fig. 4, where the rctractor S,instead of being attached to a fixed support, is attached to thearmature-lever L of the starting-magnet G. The retractor S for L isstrong enough to overcome the tension of S and to give to the latter thenormal tension required in the ordinary operation of L. When, however,the magnet G is energized, the armature L is drawn up, thus slackeningthe tension of S, so that the current flowing in magnet-coil K at thestart will be sufficient to pull down lever L and start the lamp; or thecoil G may act to lower'the clutch 0 independently of a descent of L.This is shown in Fig. 5, where the lover L carries the magnet G, whosearmature-lever L lowers 0 when attracted against the force of the springS. After contact at E E, G is open-circuited, as before, and, releasingits armature L, an arc is formed at E E, the regulation of which isafterward eifected by variations of K alone acting on the armature B Bupon L and against the spring S. If de sired, the coil or magnet G mayat the start lower both the magnet K and its armature, as indicated inFig. 6, where K is shown as mounted in an armature-lever L for G,whichat the start lowers K and also slackens the re tractor S for L. WVhen Gbecomes inactive, retractor S raises K, and at the same time gives to Sthe proper tension. If desired, the coil G may act as anelectro-thermo-motorde vice through the increase of temperature in itdue to the passage of current through it. This may be accomplished bythe device shown in Fig. 7, where the coil G is shown inclosed in acylinder containing air or other fluid expansible by heat, and thepiston of said cylinder is arranged to exert a pressure upon the leverL, so as to lower the same and start the lamp, when the fluid expands byheat developed in G acting as a resistance.

' A compound bar might be substituted for the It is to be understoodthat lamps containing gear-trains may be operated in accordance with ourinvention, providedonly that their mechanism can be put under thecontrol of an armature B B or equivalent axial core.

That We claim as our invention is= 1. The combination, in an electriclamp, of a stationary high-resistance derived circuit magnet, anarmature therefor, a lever carrying said armature and supporting theelectrode and actuated in opposite directions by said derived-cireuitmagnet and a suitable retractor, a starting or assisting coil Wound onthe same fixed core with the derived-circuit coils and placed in anauxiliary or independent branch around the carbons closed When thecircuit through the carbonsisbroken, and means for breaking saidauxiliary branch placed in a circuit closed through the carbons whenthey come together.

2. The combination, in an electric lamp, of a high-resistancederived-circuit magnet, a carbon-supporting and feed regulatingmechanism actuated by said magnet in opposition to a suitable retractor,astationary auxiliary or starting coil-upon the same core with thehigh-resistance coil, and means for cutting out or rendering saidauxiliary or starting coil inactive placed in a circuit completedthrough the carbons.

3. The combination, in an electric lamp, of a fixed high-resistancederived circuit mag= net having a conical pole, a perforated ar mature,feed-regulating mechanism actuated thereby in opposition to a suitableretractor in a direction to lower the carbon and at the same time causea feed upon an increase in the length of are, a fixed auxiliary startingor assisting coil acting on the armature-lever in the same direction asthe derived-circuit coil and placed in a circuit closed when the lamp isout of action, and means for cutting out or rendering said coil inactiveplaced in a circuit closed only through the carbons.

4. The combination, in an electricarc lamp, of a derived-circuit magnet,a feed-regulating mechanism engaging with and normally supporting thecarbon-carrier, a support for said mechanism acted upon by said magnetin a direction to lower the carbon, a retractor tending to lift thesupport, and three independent branches or circuits, one including thederived circuit magnet, another a starting coil or circuit, and thethird including the carbons and a switching-m agnet, by which thestarting coil or circuit is switched out of operation on theestablishment of circuit through the carbons.

5. The combination, in an electric-arc lamp, of a high resistancederived-circuit magnet, an armature lever therefor supporting the carbonelectrodes and actuated in opposite directions by said magnet and by asuitable retractor, a starting coil or circuit on the core of saidderived-circuit magnet, a circuit-controller for throwing saidstarting-coil out of action, and a magnet in the carbon branch and in acircuit independent of the derived circuit magnet for operating saidcircuit-controller.

Signed at Lynn, in the county of Essex and State of Massachusetts,this28th day of December, A. D. 1883.

ELIHU THOMSON.

E. WILBUR RICE.

Witnesses:

W. O. WAKEFIELD, E. B. DOEN.

